Professor of Ethology, Cambridge University; Co-author, Design for a Life

Changing my Mind

Near the end of his life Charles Darwin invited for lunch at Down House Dr Ludwig Büchner, President of the Congress of the International Federation of Freethinkers, and Edward Aveling, a self-proclaimed and active atheist. The invitation was at their request. Emma Darwin, devout as ever, was appalled by the thought of entertaining such guests and at table insulated herself from the atheists with an old family friend, the Rev. Brodie Innes, on her right and with her grandson and his friends on her left. After lunch Darwin and his son Frank smoked cigarettes with the two visitors in Darwin's old study. Darwin asked them with surprising directness: "Why do you call yourselves atheists?" He said that he preferred the word agnostic. While Darwin agreed that Christianity was not supported by evidence, he felt that atheist was too aggressive a term to describe his own position.

For many years what had been good enough for Darwin was good enough for me. I too described myself as an agnostic. I had been brought up in a Christian culture and some of the most rational humanists I knew were believers. I loved the music and art that had been inspired by a belief in God and saw no hypocrisy in participating in the great carol services held in the Chapel of King's College Cambridge. I did not accept the views of some of my scientific colleagues that the march of science has disposed of religion. The wish that I and many biologists had to understand biological evolution was not the same as the wish had by those with deep religious conviction to understand the meaning of life.

I had, however, led a sheltered life and had never met anybody who was aggressively religious. I hated, of course, what I had read about the ugly fanaticism of all forms of religious fundamentalism or what I had seen of it on television. However, such wickedness did not seem to be simply correlated with religious belief since many non-believers were just as totalitarian in their behaviour as the believers. My unwillingness to be involved in religious debates was shaken at a grand dinner party. The woman sitting next to me asked me what I did and I told her that I am a biologist. "Oh well," she said, "then we have plenty to talk about, because I believe that every word of the Bible is literally true." My heart sank.

As things turned out, we didn't have a great deal to talk about because she wasn't going to be persuaded by any argument that I could throw at her. She did not seem to wonder about the inconsistencies between the gospels of the New Testament or those between the first and second chapters of Genesis. Nor was she concerned about where Cain's wife came from? The Victorians were delicate about such matters and were not going to entertain the thought that Cain married an unnamed sister or, horrors, that his own mother bore his children, his grand children and so on down the line of descendants until other women became available. Nevertheless, the devout Victorians were obviously troubled by the question and they speculated on the existence of pre-Adamite people, angels probably, who would have furnished Cain with his wife.

My creationist dinner companion was not worried by such trivialities and dismissed my lack of politesse as the problem of a scientist being too literal. However, being too literal was not my problem, it was hers and those of her fellow creationists. She was hoist on her own petard. In any event, it was quite simply stupid to try to take on science on its own terms by appealing to the intelligence implicit in natural design. Science provides orderly methods for examining the natural world. One of those methods is to develop theories that integrate as much as possible of what we know about the phenomena encompassed by the theory. The theories provide frameworks for testing the characteristics of the world — and though some theorists may not wish to believe it, their theories are eminently disposable. Facts are widely shared opinions and, every so often the consensus breaks — and minds change. Nevertheless it is crying for the moon to hope that the enormous bodies of thought that have been built up about cosmology, geology and biological evolution are all due to fall apart. No serious theologian would rest his or her beliefs on such a hope. If faith rests on the supposed implausibility of a current scientific explanation, it is vulnerable to the appearance of a plausible one. To build on such sand is a crass mistake.

Not long after that dreadful dinner, Richard Dawkins wrote to me to ask whether I would publicly affirm my atheism. I could see no reason why not. One of the clear definitions of an atheist is a lack of a belief in a God. That certainly described my position, even though I am disinclined to attack the beliefs of the sincere and thoughtful people with strong religious beliefs whom I continue to meet. I completed the questionnaire that Richard had sent to me. I had changed my mind. A dear friend, Peter Lipton, who died suddenly in November 2007, had been assiduous in maintaining Jewish customs in his own home and in his public defence of Israel. After he died I was surprised to discover that he described himself as a religious atheist. I should not have been surprised.